exam 1 Flashcards
(70 cards)
What are the main components of the Central Nervous System (CNS)?
Brain and spinal cord
The brain is located within the cranial cavity, while the spinal cord is located within the spinal vertebral column.
What does the Peripheral Nervous System (PNS) consist of?
Nerves located outside cranial and vertebrae column
It includes sensory and motor nerves that connect the CNS with the rest of the body.
What is the role of afferent nerves in the Somatic Nervous System (SNS)?
Bring in stimuli from external to CNS
Examples include stimuli from skin, skeletal muscles, joints, and eyes.
What is the role of efferent nerves in the Somatic Nervous System (SNS)?
Motor signals to move skeletal muscles from CNS
Efferent nerves are responsible for voluntary movements.
What is the function of the Autonomic Nervous System (ANS)?
Interacts with internal environment
It regulates involuntary bodily functions.
What are the two divisions of the ANS?
Sympathetic and parasympathetic nerves
Each division has distinct roles in responding to stress and relaxation.
What are the characteristics of sympathetic efferent nerves?
First stage neurons are short, second stage neurons are longer
They stimulate and mobilize energy resources in response to threats.
What is the role of parasympathetic efferent nerves?
Conserve energy and promote psychological relaxation
Their first stage neurons exit from the brain and sacral spinal cord.
How many cranial nerves are there?
24 cranial nerves
12 exit from the right hemisphere and 12 from the left hemisphere.
What is the function of the meninges?
Three layers of tissue that protect the CNS
The layers are dura mater, arachnoid, and pia mater.
What is the purpose of cerebrospinal fluid?
Provides support and cushioning to the brain
It is housed within the ventricles and subarachnoid space.
What is the blood-brain barrier?
Barrier between blood vessels and neural tissue
It prevents toxins from entering the brain and regulates the flow of essential substances.
What are the main components of a neuron?
Dendrites, axon, cell body (soma), synaptic buttons
Neurons transmit signals and communicate through synapses.
What distinguishes unipolar, bipolar, and multipolar neurons?
Based on the number of extensions from the cell body
Unipolar has 1 extension, bipolar has 2, and multipolar has more than 2.
What is a nucleus in the context of the CNS?
Group of cell bodies within the CNS
It is analogous to ganglia in the PNS.
What are the types of glial cells?
Oligodendrocytes, Schwann cells, microglia, astrocytes
Each type has distinct roles in supporting and protecting neurons.
What is the function of oligodendrocytes?
Myelinate axons in the CNS
They have many extensions that cover multiple axons.
What is the role of astrocytes?
Support neurons and regulate blood supply
They are involved in the blood-brain barrier and chemical movement.
What are the three axes of the nervous system?
Longitudinal, dorsoventral, mediolateral
These axes help describe the orientation and structure of the nervous system.
What are the five groups of spinal levels?
Cervical, thoracic, lumbar, sacral, coccygeal
There are a total of 31 spinal levels.
What characterizes the dorsal and ventral horns of the spinal cord?
Dorsal horn contains grey matter; ventral horn contains motor neurons
The dorsal root brings sensory information, while the ventral root carries motor commands.
What is the primary function of the medulla?
Regulates basic physiological reflexes
- consists of recticular formation: formation of relay neurons which maintain appropriate level of arousal to environment
- regulates circadium rythym
It is part of the myelencephalon.
What structures are found in the midbrain?
Tectum and tegmentum
(compose the Mesencephalon)
They are involved in sensory processing and motor control.
What does the thalamus do?
Processes and relays sensory information to the cerebral cortex
It consists of two lobes connected by the massa intermedia.
